The conventional thickness shear type piezoelectric vibrator is formed by mechanical working and its shape is restricted to a disc type. However, the disc type vibrator is of such large dimensions that it is not suitable for use in wrist-watches.
Recently a rectangular type vibrator has been developed as an improvement of the disc type. However, in a small sized vibrator of this construction the energy loss in the supporting portion is very large and sufficient performance is not obtained. Moreover, by reason of insufficiencies in the supporting structure, a sub-vibration is frequently generated whereby the frequency-temperature characteristics of the vibrator are very bad.